I bought rx580 gpu that has been used for 2 months of mining. It works, so i played a bit of world of tanks but like 2 hours later i tried to play overwatch, when i got into match the gpu just turns off, i installed the drivers and still nothing is working. Then i turned on gta 5 and saw that the graphics looked worse than with my 760, anyone knows why is this and can i fix it?
Because you bought a mining card and assumed it was fine after running just one game?
You can't fix it as far as I know - get your money back.
You know it was mined on and that they claimed it was for 2 months - or so they said... What you don't know is how extensively they mined on it for.
4 hours a day? 8 hours? 12? 24/7, until mining became unprofitable?
But just to give the mining card the benefit of the doubt... what's the make and model of the power supply, and for how long has it been in use?
Post the rest of your PC's specs too.